On 26 Apr 2017, at 22:38, Brent Meeker wrote:
On 4/26/2017 7:28 AM, Bruno Marchal wrote:
On 26 Apr 2017, at 00:19, Brent Meeker wrote:
On 4/25/2017 1:59 AM, Bruno Marchal wrote:
On 25 Apr 2017, at 01:13, Bruce Kellett wrote:
On 24/04/2017 6:07 pm, Telmo Menezes wrote:
On Mon, Apr 24, 2017 at 6:08 AM, Russell Standish <li...@hpcoders.com.au
> wrote:
On Sun, Apr 23, 2017 at 11:49:51AM +0200, Telmo Menezes wrote:
Ok, so you are rejecting computationalism. Computationalism
is the
hypothesis that our mind supervenes on computations (sorry
Bruno, it's
easier to write for the purpose of this discussion :). You are
declaring that mind supervene on the physical brain.
That is not it at all. We've clarified with Bruno many times
that
computational supervenience is compatible with physical
supervenience. Which is just as well, as otherwise it would be
so much
the worse for computationalism.
I have no doubt that the brain is a physical computer, and that
computations performed by the brain are no different from any
other
computations.
We are discussing physicalism and computationalism, and if they
are
compatible or not, correct?
Bruce repeatedly makes variation of the claim: "look, the brain
is
physical and the brain generates consciousness, these are the
facts".
This is what I am replying to. It's an argument from authority
that
leaves no space for debate or reasoning.
First, it is not an argument from authority, it is an argument
made on the basis of all the available evidence -- consciousness
supervenes on the physical brain.
Second. An argument from authority is not necessarily a reason
to reject that argument. Because life is short and we cannot be
experts in absolutely everything, we frequently have to rely on
authorities -- people who are recognized experts in the relevant
field. I am confident that when I drive across this bridge it
will not collapse under the weight of my car because I trust the
expertise of the engineers who designed and constructed the
bridge. In other words, I rely on the relevant authorities for
my conclusion that this bridge is safe. An argument from
authority is unsound only if the quoted authorities are
themselves not reliable -- they are not experts in the relevant
field, and/or their supposed qualifications are bogus. There are
many examples of this -- like relying on President Trump's
assessment of anthropogenic global warming, etc, etc.
Third, since it is now clear that the term "physicalism" refers
to the belief in primary matter, I have never ascribed to
"physicalism".
Usually I use "Weak materialism" for the "assumption/belief" in
primary matter. primary means "in need to be assumed"; Something
is "primary" if to get its existence we need to assume it, or
something equivalent. For example, we know since the failure of
logicism that numbers are primary. We cannot derive them from
logic.
But we can - and did - derive them from observation and
manipulation of objects. Numbers came from measuring the size of
sheepherds, the steps from one place to another,... You learned
them that way at your mother's knee.
I was using "derivation" in the logical or mathematical sense. Size
of sheepherds can be used for illustration, but if you think we can
derive numbers from sheep, show me a theory of sheepherds not using
numbers, and then a logical derivation of number existence from that.
Haven't you read Gamow's "One, Two, Three, Infinity".
Yes. Lovely book, but slightly responsible for my early belief in wave
reduction ...
The point is that to derive numbers from sheepherds in the logical
way, you would need to define sheep in first order logic, and this as
primitive (not using numbers, nor sets, etc.). That is simply
ridiculous. I cannot even conceive one axiom apt to that task.
It is a bit like the difference between we derive atoms from the
observation all around us, and we explain the origin of atoms from
the consumption of star.
What you said is correct, but not relevant in the search of a
fundamental theory.
You only think so because you assume that arithmetic and logic are
fundamental.
You need some amount of that idea to even define computationalism, or
just Church-Turing thesis, universal number, etc. Physicist assumes
this too.
Of course, we can derive them from the combinators theory, but
combinators are Turing equivalent to the numbers.
Weak materialism is just the belief in some matter, and that
matter cannot be explained by something non material.
I must used "weak" before materialist, because the term
"materialist" has a special meaning in philosophy of mind: it
means that only matter "really" exist, ad is opposed to dualism
(matter and mind exists) and immaterialism monism (only
immaterial objects exist)
Physicalism is the assumption, in metaphysics/theology, that
physics is the fundamental science to which all other sciences
can be, in principle, reduced.
We can conceive some forms of physicalism which are
immaterialist, for example Tegmark is close to this. But usually,
most physicalist are weak materialist, and often I use weak
materialism and physicalism as being quasi the same thing.
I am an empirist, indeed, I extracted "computationalism" from
biology, well before I knew about Church and Turing. And I take
physics very seriously, and as the ultimate judge. Indeed, my
point is that if mechanism is correct, the physical reality is
"in the machine's head", and that is what makes mechanism
testable: by comparing the physics in the head of the machine
with the physics inferred from the observation.
Testable requires not comparison, but falsifiability. So if
computationalism predicts things that are not observed, as it must
if it is to explain thoughts, then it seems it if falsified. It
is saved only by the too cheap trick of saying everything exists.
Not everything, just 0 and the successors.
Then we get all computations as a theorem, and all the rest as
computation
No, you also require addition, multiplication, induction, rules of
inference and the UD and the realism of arithmetic.
Arithmetical realism is enough, except for the modus ponens rule.
Induction is not assumed.
"Getting a theorem" is only showing there is a truth preserving
inference chain from some axioms.
yes. And RA proves the existence of the computations.
seen from the first person self-referential pov of the machines
emulated by those computation.
But those "persons" are characterized entirely by "beliefs" about
arithmetic.
Why. The theorem saying that ZF proves infinity is also a theorem of
arithmetic. Likewize, the theorem saying that Brent sent me this mail
and believes this or that, belongs also to elementary arithmetic
(although the proof might be long and deep). Most arithmetical
creature believes in much more than arithmetic.
We judge theories by how well they predict the world we observe.
Then physics fails up to now, and at least we know why, because we
know that if the physical reality is primary, we need a non
computationalist theory of mind, but are not even close to have
anything like that.
bruno
I don't see any persons like that.
Brent
--
You received this message because you are subscribed to the Google
Groups "Everything List" group.
To unsubscribe from this group and stop receiving emails from it,
send an email to everything-list+unsubscr...@googlegroups.com.
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at https://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/d/optout.
http://iridia.ulb.ac.be/~marchal/
--
You received this message because you are subscribed to the Google Groups
"Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to everything-list+unsubscr...@googlegroups.com.
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at https://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/d/optout.
